Dystonia is a neurological disorder characterized by excessive involuntary muscle contractions leading to twisting movements and unnatural postures. It has many different clinical manifestations, and many different causes. Individually each subtype of dystonia is quite rare, but collectively there are more than three million affected people worldwide. Unfortunately, there are few effective medical treatments, and surgical interventions, while effective in some forms of dystonia, are not broadly indicated and carry the risks inherent to invasive procedures. Fortunately, however, several promising pharmacological agents recently have been discovered by laboratory screening programs and should be available for clinical evaluation in the near future. Moreover, several pharmaceutical companies also have expressed interest in clinically evaluating drug candidates in dystonia. A major barrier to moving forward with these potential new treatments is uncertainty regarding the most efficient designs for clinical trials in dystonia. This uncertainty exists in part because the term 'dystonia denotes a group of rare and heterogeneous disorders for which there is limited prior clinical trial experience. The goal of our workshop is to develop recommendations for clinical trial designs best-suited for the dystonias. The workshop will bring together clinicians involved in treating and studying dystonia, clinical trialists from other neurological disorders, biostatisticians, junior trainees, and experts from the FDA. The main outcome of the workshop will be a summary of the status of clinical trials for dystonia, identification of missing elements necessary for initiaing optimal clinical trials in dystonia, recommendations for future research needed to address any obstacles to clinical trials in dystonia, and one or more designs that may be appropriate for future trials. The results will be shared with the clinical research community in the form of a professional journal publication. PUBLIC HEALTH RELEVANCE: The importance and relevance of this project stems from the fact that dystonia is considered the third major movement disorder affecting hundreds of thousands of Americans and that there is no cure for this disease. Moreover, dystonic symptoms are prevalent among patients suffering from other major neurological disease: Parkinson's disease, Huntington's disease, and many others. Designing and conducting clinical trials in this field is desperately needed to facilitate and speed up therapeutics discovery.